For general interest, just in case the need arises.

Cotronics makes a variety of high temperature Adhesives.

Within the list of Ceramic Adhesives are Metallic adhesises as well.
A general metal bond is Durabond 950 good to 1200 deg. F.
The data sheet shows a comparison to epoxy.


Cotronics, High temperature adhesives
http://www.cotronics.com/vo/cotr/ca_1.htm
http://www.cotronics.com/vo/cotr/ca_metallic.htm
Rolf

Thanks Rolf!

Paul and I were talking about aluminum center and end housings
this past wed. , the problem with aluminum housings is creating
a durable surface for the rotor side seals to ride on. The oem
cast iron housings are surface hardened and precision ground,
creating a surface similar to the bore piston rings move within.
The grinding process leaves minor surface scratches within which
a thin film of oil is maintained.

 Aluminum is not tough enough to withstand the constant
pressure of the rotor seals moving against it. Paul stated, and
he will correct me if I heard him wrong, that Mazda used the
process called Detonation Gun Coating on the16b prototype engine
to resolve the wear problem. I believe he also stated that the
Mazdatrix aluminum end and center housings were constructed
similarly. I did'nt think to ask about what Mazda did with
magnesium housings, which I believe were used on the 91 LeMans 4
rotor.

 As my process of learning about the technical difficulties of
creating rotary engines has progressed, I have considered as
many ways as I could think of, to get what I want in my personal
aircraft rotary engine. So this one issue has stayed with me;
How do I create the lightweight housings using my own skills and
equipment? I have no desire to spend the several thousand
dollars required to get a product that might not work on
aircraft.

 The ceramic adhesives may do the trick. I considered oven
brazing cast iron plates to each side of a pre machined (for
coolant and oil) aluminum center section. There are metals that
can bond them together. The melting point of the metals is
perhaps to low, at around 450f.

 With the ceramic adhesives, it appears a high strength bond
between the iron plate, and the machined aluminum (or perhaps
magnesium) center section may be possible. With an engine
operating temperature approximating 190f, the bond strength of
the ceramic adhesive exceeds 800psi.; and then gets higher as
the temperature  increases.

I am not certain, but it appears to me that any expansion
contraction differences between the iron and aluminum, may not
have a negative effect with a bond this strong; considering the
bonding surfaces are wide enough. With coolant pressure never
exceeding 50psi at 200f, seems like no problems could occur with
the bond at the center of the housings where there is no crush
pressure from the  housing through bolts.

Has it been tried already?
Can this resolve a significant problem of lightening the rotary engine?

Ed Carver

Sounds like it is worth a try Ed. If the water jacket is open
on one side it can be machined on an NC mill. Use the adhesive
to seal the various chambers to the wear plate. Here are some
3D's,dwg and pictures on the subject. Richard Sohn uses several
high temp O-rings.


Paul Lamar